Power locking driye chuck



May 0, 1950 R. E. SCHULZ 2,509,888

POWER LOCKING DRIVE CHUCK Filed July 7, 1947 2 Sheets-Sheet l w El i-I as? I N VEN TOR.

May 3%, W5@ R. E. SGHULEI POWER LOCKING DRIVE cam;

2 Sheets-Sheet 2 Filed July '7', 1947 Patented May 30, 1950 :PDWERLQCKING DRIVE UHUGK Richatd E; Sch1i1zi='Saginaw, Mich.,- assignorio .Wickes Bros, Saginaw, -Mich.

Apjilication.'llilly'7,..l947,' Serial No. 759,331

J This inventionrelates to :work-hblding-devices for lathes, and-more particularly to' a power looking drive chuckif or firmly gripping'a crankshaft inga center drive. type crankshaft lathe.

"one ofthe prime objects of the invention is to designa chuck which is. rapid. in" itslockin' and unlocking operation, powerfulin-"clamping action, sothatit securely holdsthe crankshaft in proper position, and whichis"fully"automatic;.in its operation.

Another objectof the invention is to provide a power lockingdrivechuck, composedzof few Parts, all of whichare of sturdy, substantial construction, and which can be'readily manufactured. and assembled.

-A further object isto provide. a :chucki having ample throat opening, so that a rough, unfinished crankshaft can be readily loadedgandlocked in position, and from which. thefini'shed shaft can be easily removed, without marring or endangering the finish.

.A further object still .is .to provide a sturdy, quick-acting clamping means whichfirmlygrips an'dboldsthe crankshaftin accurate centered position in a lathe, eliminating .any .so-called hogging in of the tools during the-machining operation and the, possibility ..of twisted, .broken stock and. rejects.

4T0 the accomplishment of the foregoing and related ends, said inventionthen. consistsinthe means hereinafter more fully described, particularly-pointed out inthe-appended claims and annexed drawings, the following description setting forth, in detail, certain means-and one mode of carrying out the invention, such disclosed means and mode illustrating, however, but one of the various ways in which the principle of the invention may be used.

In the drawings:

:Figzl is an axial view of thesside of theroenter drive .powerchucking device ti-ncorporatil rg the principles .and features of the a-invention, and showing, in? broken lines, a crankshaft locked in position therein.

Fig. 2 is a part-sectional, top plan view illustratingthe Worm and worm wheel mechanism.

"Fig.8 is a view .similarito l ig. #1, parts being broken away to show the construction, the clamp ing jaw being shown in open position to illustrate the clear, unobstructed space to permit loading and unloading of the crankshaftv Fig. 4 is a part-sectional, edge-elevational view taken on the line 4-4 of Fig. 3.

Referring now more specifically to the drawings in which I have shown, for the purpose of illus- .2 tration, :a chuck bddy or -carrier :member This is disc-shaped as shown in 'Flgs. llsand 3'10! the-drawings; and is of a size 1 to L accommodate the workto be machined.

The web por'tion t of the chuck "body formed with a removable, pre-ma'chined bushing "9 :in which the pro-machined and ground wrank counter balanced web of the crankshaft Kris mounted, said crahkshaiftbeing locatedron the airis'of rotation rum thelathe,:the-endsof the crankshaft 11 being supported in the usual lathe centers (not shown), and I do not deem itneoessary to show or describe the lathe; as the instant application is directed to :the chuck-mechanism only.

Anangularly disposed "surface; I I is provided-at the one end of the-'removahle bushing *membeniQ, airman-abutment clampl' Z is mounted thereon, said clamp being formed-with a depen'dingrou-nded section l3-whic'h snugly fits-a groove provided *on the surface I l to secure it in' position. A depending shoulder $5: is "formed *on the opposite end of the clarnp 12, thisshoul dered endoverhanging theone end *oftheflon'shing 9, studs i445 being threaded in -said web, and nuts l8 serve to secure the clamp tothe chu'ck; theabutinent being adjustable to=suit cranks of 'diii'erentdimensions.

Aclamping jaw i 9' is pivotally'connected" to the bifurcated end 20 of the chuck body by means'of a pin 2! the ends of the pin bein-gmounted in enlarged" openings 22 formed in the bifurcated sections *to provide "the necessary :movement of the jaw-*dur-ing the-locking and nnlocking operation.

."Ahardened -land 2 3is provided onthefree end of the "jaw "'for engagement with the crank: and a cam plate P is provided directly below the hinge pin to maintain the hinged end of the :jaw in position. i

The jaw actuating mechanismis "cl-early shown in Figs? and "3 of the drawings, and comprises a hOriZOIltSQHydiSPOSGdW01m24 jOl12rIa1ediH SlZ-ltable bearings 25 provided in'the chuck body: said worm meshing with and drivinga wormwheel '26 which is mounted on a *shaft -Z'L- said shaft being journaled in bearings 2 8 with its "one =end sectionthreadedas at 29.

A'vertically disposed bore 30 isprovided in the chuck body as shown, and an interiorly threaded connecting rod 3! is reciprocatingly mounted therein and has threaded engagement with the threaded section 29 of I the shaft, the upper end of said rod being pivotally connected to the clamping jaw l9 at a. point intermediate its length by means of a pin 32.

The worm 24 is driven by means of a gear 33 which is mounted on the end of the worm shaft 34 and can be connected to any suitable source of power, so that it can be automaticall controlled in any desired manner.

The abutment clamp I2, when set, usually remains in adjusted position, the end of the clamp overhanging the end of the pre-machined surface 9, and when the crankshaft K is loaded in the lathe, the shouldered section N bears against the depending shoulder 15 of the clamp; then when the automatic control (not shown) is actuated to drive the gear 33, the worm, worm wheel and shaft 24, 26, and 21 respectively will be driven, and the connecting rod 3| will be forced downwardly so that the free end of the clamping jaw l9 engages the opposite shoulder M on the web W; this forces the shoulder N against the clamp [12, and continued movement of the jaw firmly secures the web against the bushing 9 so that the crankshaft will be accurately secured in true centered position in th lathe.

After the machining operation is completed, the sequence is reversed, the clamping jaw 19 being swung upwardly so that the finished crankshaft can be readily removed. The locking and unlocking action is ver rapid and fully automatic, and the chuck firmly and accurately secures the crankshaft in position.

Having thus set forth and described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a center drive crankshaft chuck, a work carrier member having a pre-machined bushing engageable with the shouldered web of a crankshaft, a work-engaging abutment member forming a projecting end wall at one end of said bush-'- ing, and engaging a shoulder of the crankshaft to one side of the axis of rotation of the crankshaft, a work-engaging clamping jaw hingedly connected to the chuck adjacent the opposite end of the bushing for engagement with an opposed shoulder on the opposite side of the axis of roe tation of the crankshaft, a connecting rod pivotally connected to said jaw at a point intermediate its length, and power-actuated driven means engageable with said rod to adjust it vertically and swing the jaw to locked and unlocked position.

2. The combination as defined in claim 1 in which th hinged end of the jaw is loosely connected to said chuck, said jaw tending to rotate the-crankshaft and firmly clamp the crankshaft web against said bushing.

3. The combination defined in claim 1 in which the connecting rod is threaded, a threaded shaft having threaded engagement with said rod, and means for driving said shaft for reciprocating said connecting rod.

4. Th combination set forth in claim 1 in which the work-engaging abutment member is adjustable with relation to the bushing, and a rib on the clamp and engageablewith the chuck to anchor it in position.

5. In a center drive crankshaft comprising a work-carrier member having a pre-machined bushing provided thereon, an adjustable workengaging abutment at one end of said bushing and engaging the pre-machined ground and shouldered web of a crankshaft to one sid of the axis of rotation of the chuck, a hingedly connected clamping jaw engageable with the shouldered web of the crankshaft opposite the point of engagement of the abutment, a connecting rod connected to said jaw at a point intermediate its length, and a pinion for actuating said rod to simultaneously force the web into firm engage ment with the abutment and securel against the bushing of the work-carrier.

6. In a chucking device for machine tools, comprising a chuck body, a pre-machined, removable bushing provided thereon and adapted to receive the pre-machined and ground shouldered web of a crankshaft, a work-engaging abutment member forming a shoulder on the web of the crankshaft to one side of the axis of rotation theredf, a work-engaging clamping jaw loosely and hingedly connected to the chuck adjacent the opposite end of the bushing, and engaging a shoulder on the crankshaft web diametrically opposite to the abutment member, and a mechanically actuated, reciprocal connecting rod having a threaded shaft engageable therewith, and an oilset pinion drivingly connected to said shaft for swinging said jaw into engagement with the web of a crankshaft for locking it securely against said abutment and bushing.

7. In a chucking device for machine tools, com prising a chuck body, a pre-machined, removable bushing provided thereon and adapted to receive the pre-machined and ground shouldered web of a crankshaft, a work-engaging abutment member forming the end wall of one end of said bushing, and engageable with a shoulder on the web of the crankshaft to one side of the axis of rotation thereof, a work-engaging clamping jaw loosely and hingedl connected to the chuck adjacent the opposite end of the bushing, and engaging a shoulder on the crankshaft web diametrically opposite to the abutment member, and a threaded, mechanically-actuated reciprocable' means for swinging said jaw into engagement with the web of a crankshaft, said reciprocable means comprising a threaded connecting rod, a threaded shaft engageable therewith, a worm wheel on the shaft, and a pinion drivingly connected to the worm wheel for swinging the clamping jaw to lock and unlock said crankshaft with relation to said bushing.

RICHARD E. SCHULZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

